linux-dev/arch/sparc/configs, branch master

drivers/char: remove /dev/kmem for good

2021-05-07T07:26:34Z

Patch series "drivers/char: remove /dev/kmem for good". Exploring /dev/kmem and /dev/mem in the context of memory hot(un)plug and memory ballooning, I started questioning the existence of /dev/kmem. Comparing it with the /proc/kcore implementation, it does not seem to be able to deal with things like a) Pages unmapped from the direct mapping (e.g., to be used by secretmem) -> kern_addr_valid(). virt_addr_valid() is not sufficient. b) Special cases like gart aperture memory that is not to be touched -> mem_pfn_is_ram() Unless I am missing something, it's at least broken in some cases and might fault/crash the machine. Looks like its existence has been questioned before in 2005 and 2010 [1], after ~11 additional years, it might make sense to revive the discussion. CONFIG_DEVKMEM is only enabled in a single defconfig (on purpose or by mistake?). All distributions disable it: in Ubuntu it has been disabled for more than 10 years, in Debian since 2.6.31, in Fedora at least starting with FC3, in RHEL starting with RHEL4, in SUSE starting from 15sp2, and OpenSUSE has it disabled as well. 1) /dev/kmem was popular for rootkits [2] before it got disabled basically everywhere. Ubuntu documents [3] "There is no modern user of /dev/kmem any more beyond attackers using it to load kernel rootkits.". RHEL documents in a BZ [5] "it served no practical purpose other than to serve as a potential security problem or to enable binary module drivers to access structures/functions they shouldn't be touching" 2) /proc/kcore is a decent interface to have a controlled way to read kernel memory for debugging puposes. (will need some extensions to deal with memory offlining/unplug, memory ballooning, and poisoned pages, though) 3) It might be useful for corner case debugging [1]. KDB/KGDB might be a better fit, especially, to write random memory; harder to shoot yourself into the foot. 4) "Kernel Memory Editor" [4] hasn't seen any updates since 2000 and seems to be incompatible with 64bit [1]. For educational purposes, /proc/kcore might be used to monitor value updates -- or older kernels can be used. 5) It's broken on arm64, and therefore, completely disabled there. Looks like it's essentially unused and has been replaced by better suited interfaces for individual tasks (/proc/kcore, KDB/KGDB). Let's just remove it. [1] https://lwn.net/Articles/147901/ [2] https://www.linuxjournal.com/article/10505 [3] https://wiki.ubuntu.com/Security/Features#A.2Fdev.2Fkmem_disabled [4] https://sourceforge.net/projects/kme/ [5] https://bugzilla.redhat.com/show_bug.cgi?id=154796 Link: https://lkml.kernel.org/r/20210324102351.6932-1-david@redhat.com Link: https://lkml.kernel.org/r/20210324102351.6932-2-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Kees Cook Cc: Linus Torvalds Cc: Greg Kroah-Hartman Cc: "Alexander A. Klimov" Cc: Alexander Viro Cc: Alexandre Belloni Cc: Andrew Lunn Cc: Andrey Zhizhikin Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Brian Cain Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Chris Zankel Cc: Corentin Labbe Cc: "David S. Miller" Cc: "Eric W. Biederman" Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Greentime Hu Cc: Gregory Clement Cc: Heiko Carstens Cc: Helge Deller Cc: Hillf Danton Cc: huang ying Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: "James E.J. Bottomley" Cc: James Troup Cc: Jiaxun Yang Cc: Jonas Bonn Cc: Jonathan Corbet Cc: Kairui Song Cc: Krzysztof Kozlowski Cc: Kuninori Morimoto Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Luc Van Oostenryck Cc: Luis Chamberlain Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Mike Rapoport Cc: Mikulas Patocka Cc: Minchan Kim Cc: Niklas Schnelle Cc: Oleksiy Avramchenko Cc: openrisc@lists.librecores.org Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: "Pavel Machek (CIP)" Cc: Pavel Machek Cc: "Peter Zijlstra (Intel)" Cc: Pierre Morel Cc: Randy Dunlap Cc: Richard Henderson Cc: Rich Felker Cc: Robert Richter Cc: Rob Herring Cc: Russell King Cc: Sam Ravnborg Cc: Sebastian Andrzej Siewior Cc: Sebastian Hesselbarth Cc: sparclinux@vger.kernel.org Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Steven Rostedt Cc: Sudeep Holla Cc: Theodore Dubois Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Viresh Kumar Cc: William Cohen Cc: Xiaoming Ni Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sparc: sparc64_defconfig: remove duplicate CONFIGs

2021-03-10T00:22:40Z

After my patch there is CONFIG_ATA defined twice. Remove the duplicate one. Same problem for CONFIG_HAPPYMEAL, except I added as builtin for boot test with NFS. Reported-by: Stephen Rothwell Fixes: a57cdeb369ef ("sparc: sparc64_defconfig: add necessary configs for qemu") Signed-off-by: Corentin Labbe Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

2021-02-23T23:09:53Z

Pull sparc updates from David Miller: "A host of mall cleanups and adjustments that have accumulated while I was away, nothing major" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: (26 commits) sparc: make xchg() into a statement expression sparc64: Use arch_validate_flags() to validate ADI flag sparc32: Fix comparing pointer to 0 coccicheck warning sparc: fix led.c driver when PROC_FS is not enabled sparc: Fix handling of page table constructor failure sparc64: only select COMPAT_BINFMT_ELF if BINFMT_ELF is set tty: hvcs: Drop unnecessary if block tty: vcc: Drop unnecessary if block tty: vcc: Drop impossible to hit WARN_ON sparc: sparc64_defconfig: add necessary configs for qemu sparc64: switch defconfig from the legacy ide driver to libata sparc32: Preserve clone syscall flags argument for restarts due to signals sparc32: Limit memblock allocation to low memory sparc: Replace test_ti_thread_flag() with test_tsk_thread_flag() sbus: char: Remove meaningless jump label out_free sparc32: signal: Fix stack trampoline for RT signals sparc: remove SA_STATIC_ALLOC macro definition sparc: use for_each_child_of_node() macro sparc: Use fallthrough pseudo-keyword sparc32: srmmu: improve type safety of __nocache_fix() ...

sparc: sparc64_defconfig: add necessary configs for qemu

2021-02-19T00:17:39Z

The sparc64 qemu machines uses sunhme network hardware by default, so for simple NFS boot testing using qemu, having CONFIG_HAPPYMEAL is useful. And so we need also IP_PNP_DHCP for NFS boot. For the same reason we need to enable its storage which is a PATA_CMD64. And finally, we need CONFIG_DEVTMPFS for handling recent udev/systemd. All those options will permit to enable boot testing in both kernelCI and gentoo's kernelCI. Signed-off-by: Corentin Labbe Signed-off-by: David S. Miller

sparc64: switch defconfig from the legacy ide driver to libata

2021-02-19T00:16:17Z

Replace the ide options with the equivalent libata options. This has been carried by various downstreams like the linux-build-test repo for years already. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

arch: sparc: Remove CONFIG_OPROFILE support

2021-01-29T04:35:51Z

The "oprofile" user-space tools don't use the kernel OPROFILE support any more, and haven't in a long time. User-space has been converted to the perf interfaces. Remove the old oprofile's architecture specific support. Suggested-by: Christoph Hellwig Suggested-by: Linus Torvalds Signed-off-by: Viresh Kumar Acked-by: Robert Richter Acked-by: William Cohen Acked-by: Al Viro Acked-by: Thomas Gleixner

scsi: sr: remove references to BLK_DEV_SR_VENDOR, leave it enabled

2020-02-24T19:59:01Z

This kernel configuration is basically enabling/disabling sr driver quirks detection. While these quirks are for fairly rare devices (very old CD burners, and a glucometer), the additional detection of these models is a very minimal amount of code. The logic behind the quirks is always built into the sr driver. This also removes the config from all the defconfig files that are enabling this already. Link: https://lore.kernel.org/r/20200223191144.726-1-flameeyes@flameeyes.com Reviewed-by: Jens Axboe Signed-off-by: Diego Elio Pettenò Signed-off-by: Martin K. Petersen

sparc: configs: Remove useless UEVENT_HELPER_PATH

2019-06-13T21:12:19Z

Remove the CONFIG_UEVENT_HELPER_PATH because: 1. It is disabled since commit 1be01d4a5714 ("driver: base: Disable CONFIG_UEVENT_HELPER by default") as its dependency (UEVENT_HELPER) was made default to 'n', 2. It is not recommended (help message: "This should not be used today [...] creates a high system load") and was kept only for ancient userland, 3. Certain userland specifically requests it to be disabled (systemd README: "Legacy hotplug slows down the system and confuses udev"). Signed-off-by: Krzysztof Kozlowski Acked-by: Geert Uytterhoeven Signed-off-by: David S. Miller

configs: get rid of obsolete CONFIG_ENABLE_WARN_DEPRECATED

2019-03-08T02:32:02Z

This Kconfig option was removed during v4.19 development in commit 771c035372a0 ("deprecate the '__deprecated' attribute warnings entirely and for good") so there's no point to keep it in defconfigs any longer. FWIW defconfigs were patched with: --------------------------->8---------------------- find . -name *_defconfig -exec sed -i '/CONFIG_ENABLE_WARN_DEPRECATED/d' {} \; --------------------------->8---------------------- Link: http://lkml.kernel.org/r/20190128152434.41969-1-abrodkin@synopsys.com Signed-off-by: Alexey Brodkin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sparc64: vcc: Enable VCC module in linux

2017-08-16T04:33:50Z

Enables the Virtual Console Concentrator (VCC) module in linux kernel Signed-off-by: Jagannathan Raman Reviewed-by: Liam Merwick Reviewed-by: Shannon Nelson Signed-off-by: David S. Miller